Two 750cc injectors in the housings probably won't not deliver
enough fuel
to get to 300hp. on take-off Especially if the fuel is ethanol.
This was
the main reason (4 injectors per manifold) I considered a horizontal
slide
throttle and cast aluminum elbow with two more injectors. That and it is
easy to encased the lower injectors in a box that goes from the
housing to
the slide throttle.
Perhaps lost wax for a few units is possible. Collecting beer cans
now..
Doug Fir
The direct injection takes max advantage of the alcohol's
unique ability to cool off the charge. It also insures that
no un burned fuel goes directly out the exhaust down
past the rotor face.
There is nothing wrong
with four injectors up there. Point them in horizontally.
RB did that on the land speed record 3rd gen RX7
three rotor with three turbo chargers along with an ice
water intercooler. (268 MPH)
--
Paul Lamar ...No rotor no motor
Doug,
Not wanting to burst your bubble Doug, but if I remember correctly you
were interested in long distance travel? The R85 ethanhol blend will
shorten your range at least 20%. There just aren't the BTU's/pound in
alchol. It will burn cleaner but it will burn a bunch more fuel. The
rotary will suffer even more than a piston since you can't get the
compression beyond 9:1 NA. A turbo would be more efficient as Paul
mentioned.
Bill Jepson
Bill
The bubble is not burst yet. 20% plus is an number that unfortunately seems
to be engraved in stone and probably is true for automobiles. Real life
flying tests have proved differently. With a rotary you are correct that in
certain conditions with very pure denatured ethanol at low altitudes the
fuel mileage will suck. R-85 and A-85 seem to be quite different in
formulation however.
Baylor Univ. as well as the guys at Dakota Univ. have proved that a 12% or
less increase is possible up high and under boost. I don't know for sure
but I can imagine it has a little to do with the superior cooling of the
intake charge as such reducing the pumping losses? The only way I can hope
to have a halfway decent fuel burn of 15gal/hr @ 150 knots IAS is to go
high (15K +) go turbo, and probably go turbocompound. BTW with ferry tanks
my plane will hold 240 gallons. Plenty for the northern route.
I presently have a 2nd gen. turbo engine with 9.5:1 rotors to p-port and
get
some baseline data. Then I'll make a decision to I'll buy a Renesis 4port
and P-port it or not.
Bill I think you meant "you can't get the compression beyond 10:1 didn't
you?
Cheers
Doug Fir
What does it have to do with flying or not flying? It has to do
with BTU's per gallon.
Paul Lamar ...No rotor no motor.
Paul's right here. BTU's control your consumption requirements. You can
make your engine more efficient, but in even setups you will need about
20% more fuel. In race cars the gap is often greater than that at max
power, often 30-35%! 9.5 compression is of course the max for rotarys.
Piston engines frequently run CR's at or near 14:1 for alcohol. Not a
good idea in a gas engine since this approaches the compression ignition
point for gasoline/air mix. The only way to improve the efficiency in a
rotary will be to turbocharge. If alcohol is your intent, run a turbo
Renesis. The higher compression will help, and the turbo pressure won't
be a problem rather a boon. A turbo alcohol engine wouldn't need to be
P-ported but it would improve the efficency at high output since there
are fewer pumping losses. BTW E-85 could be E-100, the government
requires 15% gasoline as a denatureant.
Bill Jepson
Bill
OK I see where you are coming from. I wrote a quick note to the project
manager at South Dakota Univ and asked him to explain.
Perhaps the comparison test was about performance. I'll wait and see what
he says. AGE-85 is formulated with aircraft in mind, using many of the
performance enhancing additives that gasoline normally has including a wee
bit of biodiesel, whereas Baylor's E-95 (at this point) is just denatured
ethanol. Don't race cars run on methanol?
Doug Fir
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